Factory gate inflation rose twice as fast as expected last month, and the cost of raw materials soared, heaping pressure on the Bank of England to raise interest rates sooner rather than later. Evidence that pipeline inflation pressures are continuing to build will worry Bank of England policymakers at a time when consumer price inflation is nearly double its 2% target and still rising. The Office for National Statistics said producer input prices rose 13.4% on the year in January, the biggest annual rise since October 2008 and well above forecasts for an annual rate of 12.6%. Producer output prices rose 4.8% on the year, the highest annual rate since May 2010. On the month prices jumped 1%, double what economists had predicted. The ONS said the rise in input prices was mainly driven by a 28.8% annual rise in the price of crude oil, the biggest increase since May 2010. The recent rise in commodity prices also played a role. Imported metals prices were up over 26% on the year. Inflation figures have repeatedly surprised to the upside in recent months and there was little market reaction to Friday's data.